1. Field of the Invention
The present invention relates to a method of detecting a position on a touchscreen panel, a touchscreen panel, and a method of initializing a touchscreen panel.
2. Description of the Related Art
Electronic apparatuses popular at present often include a touchscreen panel. The touchscreen panel allows information to be input to electronic apparatuses through a direct touch on the touchscreen panel with a finger or the like. The touchscreen panel is expected to become more popular in the future as a simple information input device.
Most common touchscreen panels are configured to detect a contact position in response to being touched (contacted) at a single point. Accordingly, these touchscreen panels are prevented from detecting accurate position information of a contact point if being touched at two or more points. Therefore, there has been a demand for a method that makes it possible to accurately detect the position information of each contact point in the case where there are two contact points.
For example, Patent Documents 1 through 19 listed below disclose various methods of detecting contact points in the case where a touchscreen panel is contacted at two points. For example, such methods are disclosed as a method that uses a slight time difference between a first contact and a second contact, a method that connects a resistor to the conductive films of a touchscreen panel, and a method that applies voltage between X and Y electrodes.
Further, Patent Document 12 discloses a method that detects information on the distance between two points in the case where a touchscreen panel is pressed at two points. Further, Patent Document 14 discloses a touchscreen panel having divided resistive films. Further, Patent Document 17 discloses a touchscreen panel using two pairs of resistive films. Further, Patent Documents 18 and 19 disclose methods that correct a distortion in single-point inputting.    [Patent Document 1] Japanese Patent No. 3402858    [Patent Document 2] Japanese Laid-Open Patent Application No. 2009-289157    [Patent Document 3] Japanese Patent No. 3397519    [Patent Document 4] Japanese Laid-Open Patent Application No. 8-54976    [Patent Document 5] Japanese Laid-Open Patent Application No. 3-77119    [Patent Document 6] Japanese Laid-Open Patent Application No. 10-171581    [Patent Document 7] Japanese Laid-Open Patent Application No. 11-95929    [Patent Document 8] Japanese Laid-Open Patent Application No. 1-269120    [Patent Document 9] Japanese Laid-Open Patent Application No. 8-241161    [Patent Document 10] Japanese Laid-Open Patent Application No. 8-54977    [Patent Document 11] Japanese Laid-Open Patent Application No. 2007-156875    [Patent Document 12] Japanese Laid-Open Patent Application No. 2009-176114    [Patent Document 13] Japanese Patent No. 3351080    [Patent Document 14] Japanese Laid-Open Patent Application No. 9-45184    [Patent Document 15] Japanese Laid-Open Patent Application No. 2005-49978    [Patent Document 16] Japanese Laid-Open Patent Application No. 2010-102627    [Patent Document 17] Japanese Laid-Open Patent Application No. 11-232023    [Patent Document 18] Japanese Laid-Open Patent Application No. 2001-67186    [Patent Document 19] Japanese Patent No. 2554577